NSAID-induced corneal melt: Clinical importance, pathogenesis, and risk mitigation

Corneal melt, an ophthalmological condition in which corneal epithelium is lost accompanied by thinning of the corneal stroma, can lead to corneal perforation and cause loss of vision. Corneal melt is the most serious side effect of topical nonsteroidal anti-inflammatory drugs (NSAIDs), one of the topical treatments of ocular inflammation. NSAID-induced corneal melt (NICM), initially doubted, is real, having been reported by multiple groups. NICM is induced by all but one of the approved ocular NSAIDs and occurs usually in patients whose cornea is compromised by ocular surgery, diabetes, or autoimmune diseases. Its true incidence, most likely low, remains unknown. NSAID dose and duration of treatment may be important for NICM. NICM appears to evolve in two stages: the epithelial stage-marked by a corneal epithelial defect, reduced eicosanoid levels, leukocyte infiltration, and matrix metalloproteinase-facilitated desquamation-and the stromal stage, characterized by degradation of stromal collagen by activated matrix metalloproteinases. Awareness of this ominous side effect, its risk factors, and the need for prompt action once diagnosed, including NSAID discontinuation, will help mitigate the risk of NICM. Further understanding of NICM and development of efficacious treatments or safer alternatives should help eliminate this rare, but severe, side effect of ocular NSAIDs.